Image-capturing apparatus having multiple image capturing units

ABSTRACT

An image-capturing apparatus is capable of capturing a three-dimensional image and a high quality panoramic image as the need arises, and is portable if it is used as a single lens camera that captures a normal two-dimensional image. A second image-capturing unit having an image-capturing optical system is detachably connected to a first image-capturing unit, which is capable of functioning as an image-capturing apparatus by itself, through joints and a connector. The second image-capturing unit can extensively connect to other units, which have the similar connecting structure. Information is transmitted between the units through a slot for an external storage device. The positions of images captured by the second and subsequent image-capturing units can be adjusted with respect to an image captured by the first image-capturing unit. In synchronism with release signals from the first image-capturing unit, the other units are driven to capture the images at the same time or continuously.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an image-capturing apparatus,and more particularly to a portable image-capturing apparatus that iscapable of capturing a three-dimensional image and a panoramic image.

2. Description of Related Art

There has been proposed a variety of apparatuses, which capture athree-dimensional image with two optical systems provided in one camera(Japanese Patent Provisional Publication Nos. 6-273172 and 8-317424).There has also been proposed a method for selectively capturing athree-dimensional image and a normal two-dimensional image with onecamera (Japanese Patent Provisional Publication No. 8-317425).

The above-mentioned conventional apparatuses require that twoimage-capturing optical systems should be loaded in the body of thecamera, and thus, the camera is large as a whole. When capturing only anormal two-dimensional image, the camera is not portable and isdifficult to handle.

There has also been proposed an adapter that guides a right-eye imageand a left-eye image into one optical path. This adapter, however,divides effective pixels of an imaging device into two areas, and it istherefore impossible to achieve satisfactory image quality.

SUMMARY OF THE INVENTION

In view of the foregoing, it is an object of the present invention toprovide an image-capturing apparatus that is as portable as theconventional camera when capturing a normal two-dimensional image, andthat is capable of capturing a three-dimensional image and ahigh-quality panoramic image as need arises.

To achieve the above-mentioned object, the present invention is directedto an image-capturing apparatus, comprising: a first image-capturingunit having a first image-capturing optical system; and a secondimage-capturing unit having a second image-capturing optical system, thesecond image-capturing unit being detachably connected to the firstimage-capturing unit.

According to the present invention, the second image-capturing unit isdetachably connected to the first image-capturing unit, which functionsas an image-capturing apparatus by itself. In the case of the normalimage-capturing, the second image-capturing unit is detached from thefirst image-capturing unit, and only the first image-capturing unit isused. To capture the three-dimensional image and the panoramic image,the second image-capturing unit is connected to the firstimage-capturing unit to construct a multiple lens camera.

As described above, the image-capturing units are modularized so as tofreely switch the modes of the optical systems between a single lensmode and a multiple lens mode according to the purposes and conditions.The image-capturing apparatus is portable as the normal single lenscamera, and it may also be used as the multi-lens camera by connectingthe image-capturing units to increase the functions. This eliminates thewaste in the structure of the image-capturing apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

The nature of this invention, as well as other objects and advantagesthereof, will be explained in the following with reference to theaccompanying drawings, in which like reference characters designate thesame or similar parts throughout the figures and wherein:

FIG. 1 is a perspective view showing the structure of an image-capturingapparatus according to a preferred embodiment of the present invention;

FIG. 2 is a perspective back view of the image-capturing apparatus inFIG. 1;

FIG. 3 is a block diagram showing the structure of the image-capturingapparatus in FIG. 1;

FIG. 4 is a perspective view showing another embodiment of the presentinvention;

FIG. 5 is a perspective view showing an embodiment wherein threeimage-capturing units are connected; and

FIG. 6 is a perspective view showing the state wherein an electronicflash unit is connected instead of the image-capturing unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

This invention will be described in further detail by way of examplewith reference to the accompanying drawings.

FIG. 1 shows an image-capturing apparatus according to a preferredembodiment of the present invention. The image-capturing apparatus 10comprises a first image-capturing unit (a main camera) 12, whichfunctions as a camera by itself; and a second image-capturing unit 14,which is capable of detachably connecting to the first image-capturingunit 12. A taking lens 16, a finder window 17 and an electronic flash 18are provided at the front of a body of the first image-capturing unit12. A shutter release button 20 is arranged at the top of the body. Acharge coupled device (CCD) (not shown) is arranged behind the takinglens 16. Image light is formed on a light receiving surface of the CCDthrough the taking lens 16, and the CCD converts the image light into asignal electric charge corresponding to the quantity of the image light.The signal electric charge is read as an image signal in accordance witha drive pulse transmitted from a CCD drive circuit (not shown). Thenumber of pixels in the CCD should be selected according to desiredimage quality, and the CCD preferably has more than three hundred fiftythousand pixels. The imaging device is not restricted to the CCD, but itmay be an imaging device such as a metal oxide semiconductor (MOS) typeimaging device and a charge injection device (CID).

A slot 22 (equivalent to an information transmitting means and aninformation sending and receiving part) for receiving an externalstorage device 26 is formed at the right side of the firstimage-capturing unit 12 in FIG. 1. Two joint holes (equivalent to aconnecting part) are formed vertically across the slot 22, and the firstimage-capturing unit 12 is connected to the second image-capturing unit14 through the joint holes 24. Examples of the external storage device26 are a PC card, a smart medium (an image memory card), a flash memorycard and an IC card.

The second image-capturing unit 14 is provided with a taking lens 28,which is the same as the taking lens 16. As is the case with the firstimage-capturing unit 12, a CCD (not shown) is arranged behind the takinglens 28. A connector 30 (equivalent to the information transmittingmeans and a second information sending and receiving part) is providedat the left side of the second image-capturing unit 14, and two joints32 (equivalent to a connecting means) are vertically arranged across theconnector 30. The second image-capturing unit 14 can be detachablyconnected to the first image-capturing unit 12 through the connector 30and the joints 32.

In the normal image-capturing, only the first image-capturing unit 12 isused as a single lens camera, and the external storage device 26 isattached to the slot 22. In a three-dimensional image-capturing or apanoramic image-capturing, the second image-capturing unit 14 isconnected to the first image-capturing unit 12 to compose a multiplelens camera. More specifically, the joints 32 of the secondimage-capturing unit 14 are inserted into the joint holes 24 of thefirst image-capturing unit 12, and the connector 30 of the secondimage-capturing unit 14 is connected to the slot 22 of the firstimage-capturing unit 12, so that the first image-capturing unit 12 andthe second image-capturing unit 14 can connect, and the twoimage-capturing optical systems are horizontally arranged side by side.Signals and data are transmitted between both image-capturing unitsthrough the slot 22, which is originally capable of receiving theexternal storage device 26, and the connector 30.

As is the case with the first image-capturing unit 12, a slot 34(equivalent to a third information sending and receiving part) forreceiving the external storage device 26 is provided at the right sideof the second image-capturing unit 14, and two joint holes 36(equivalent to a second connecting parts) are formed across the slot 34.This enables the second image-capturing unit 14 to further be connectedto another image-capturing unit, which has the same connecting structureas the connector 30 and the joints 32. Thus, a plurality of units can beconnected sequentially.

FIG. 2 is a back view of the first image-capturing unit 12 and thesecond image-capturing unit 14, which are connected to each other. Aliquid crystal display (LCD) 40, a mode dial 42, a power switch 43, afinder eyepiece 44 are provided at the back of the first image-capturingunit 12.

The LCD 40 displays an image captured through the image-capturingoptical systems, image information read from the external storage device26 (not shown in FIG. 2), etc. For example, a 2-inch low temperaturepolysilicon LCD is used. Although not shown in detail, a parallaxbarrier display layer is formed on the surface of the LCD 40. In astereo display mode, a parallax barrier is generated on the parallaxbarrier display layer, and the parallax barrier has a pattern in whichlight transmissible parts and light shielding parts are alternatelyarranged at predetermined pitches. Strip-shaped (narrow-rectangular)image fragments, which represent a plurality of images to be displayed,are alternately arranged and displayed on an image display surface underthe parallax barrier display layer. If the image fragments represent aright-eye image and a left-eye image, a three-dimensional image can bedisplayed on the LCD 40. With this principle, an image can also bedisplayed so that it can look differently according to the viewingdirections. For example, an image pattern is formed in such a way thatimage fragments A for the first display image, image fragments B for thesecond display image, and image fragments C for the third display imageare arranged in order like A, B, C, A, B, C, A, B, C, . . . .

The mode dial 42 is disposed at a position where the thumb of the handholding the right part (a grip part) of the camera in FIG. 2 isnaturally placed. The mode dial 42 is a control means for changingfunctions (modes) of the camera. For example, marks or charactersindicating the following modes are formed at click stop positions alongthe circumference of the mode dial 42: “setup”, “self-timer”, “manualimage-capturing”, “automatic image-capturing”, “reproduction”,“erasure”, “image protection” and “connection with personal computer”. Amode is set by rotating the mode dial 42 clockwise or counterclockwisein FIG. 2 and setting the mark or the character indicating a desiredmode to an index 46.

A cross key 48 is provided at the back of the second image-capturingunit 14. The cross key 48 is a control key, which is capable of tiltingin four perpendicular directions. A concave is formed at the center ofthe cross key 48, and four marks indicating the four perpendiculardirections are formed on a slope from the edge to the central part.

Pressing an area in proximity to one of the four marks tilts the crosskey 48 to thereby input the corresponding direction (upper, lower, rightor left). The cross key 48 is a means for correcting discordance betweenthe image captured by the image-capturing optical system of the firstimage-capturing unit 12 and the image captured by the image-capturingoptical system of the second image-capturing unit 14. Operating thecross key 48 enters a direction and a displacement amount for finelyadjusting the position and the angle of the image, which is captured bythe image-capturing optical system of the second image-capturing unit14.

FIG. 3 is a block diagram showing the structure of the image-capturingapparatus according to the embodiment of the present invention. In FIG.3, the upper section is the first image-capturing unit 12, and the lowersection is the second image-capturing unit 14. The first image-capturingunit 12 comprises the taking lens 16, an imaging circuit 50, a lensdrive unit 52, an automatic control data obtaining unit 53, asynchronous signal generating circuit 54, a memory 56, an imagereproducing unit 57, a connection detecting means 58 and a controlcentral processing unit (CPU) 60. The circuits are connected to oneanother through a bus 62.

As is the case with the first image-capturing unit 12, the secondimage-capturing unit 14 comprises the taking lens 28, an imaging circuit64, a lens drive unit 66 and a memory 66. The second image-capturingunit 14 further comprises a gain adjustment circuit 70 for adjusting thegain of an image signal, and a display position adjusting device 72 foradjusting the position of the image captured by the two imaging systems.

Each of the imaging circuit 50 and 64 includes the CCD, a CDS circuit, again adjustment circuit, an A/D converter, etc. An image of a subject isformed on the light receiving surface of the CCD through the takinglenses 16 or 28, and the CCD photoelectrically converts the image, whichis sequentially read as video signals. The CDS circuit sample-holds thevideo signals read from the CCD on a pixel-by-pixel basis, and a gaincontrol amplifier amplifies the video signals. Then, the A/D converterconverts the video signals into dot-sequential RGB digital signals.

The automatic control data obtaining unit 53 includes an automaticexposure (AE) integration circuit, an automatic white balance (AWB) gaindetermining circuit, and an autofocus (AF) value determining circuit.The automatic control data obtaining unit 53 determines a photometryvalue (AE value) in accordance with the image output signals (RGBdigital signals) of one frame, which are inputted from the imagingcircuit 50. The automatic control data obtaining unit 53 determines thelevels of the RGB signals, and calculates a gain value (AWB value) insuch a way as to equalize the levels of the RGB signals. The automaticcontrol data obtaining unit 53 also determines a focus evaluation valueindicating the sharpness of the subject's image in accordance with theimage signals from the imaging circuit 50, and determines a focusposition (AF value) with the focus evaluation value. The AE value, theAWB value and the AF value are sent to the control CPU 60, and they areused for controlling the AE, the AWB and the AF.

The control CPU 60 supervises the circuits, and controls the circuits inaccordance with a variety of signals inputted from the control partssuch as the shutter release button 20 and the mode dial 42. Morespecifically, the control CPU 60 controls the exposure by setting adiaphragm and the electronic shutter values of the CCD of the imagingsystem in accordance with the AE value informed from the automaticcontrol data obtaining unit 53. The control CPU 60 sets the whitebalance by controlling the gain control amplifier in accordance with theAWB value informed from the automatic control data obtaining unit 53.The control CPU 60 also controls the lens drive unit 52 in accordancewith the AF value determined by the automatic control data obtainingunit 53 to thereby set the focusing position of the taking lens 16.

The control CPU 60 is also used as an image processing CPU, whichprocesses the image signals outputted from the imaging circuit 50 in aprocessing area of the memory 56. For example, the control CPU 60generates luminance (Y) signals and color difference (C) signals andexpands/compresses the image data.

The image reproducing unit 57 decodes the image data processed accordingto the image signals read from the imaging circuits 50 and 64; the imagedata read from the external storage device 26; and so on. The imagereproducing unit 57 supplies the decoded image data to the image displayor the LCD 40. Thus, the image captured through the CCD is displayed onthe screen of the LCD 40, and the image data stored in the externalstorage device 26 can be reproduced.

Before the control CPU 60 receives a release signal (an image-recordingstart signal) generated by pressing the shutter release button 20, etc.,a preview image (a moving or intermittent image for confirmation, whichis displayed before the image recording) is displayed on the LCD 40.Upon input of the image-recording start signal, the screen of the LCD 40freezes. In response to the input of the image-recording start signal,the image signals read from the imaging circuits 50 and 64 arecompressed as the need arises after a predetermined processing and arestored in the external storage device 26. The storage medium is notrestricted to the detachable external storage device 26, but it may alsobe an internal memory built in the image-capturing units 12 or 14. Theimage-recording start signal may also be transmitted from the outside ofthe image-capturing apparatus 10 such as a remote control and externalconnection equipment. On completion of the above-mentioned recordingprocess, the freezing state of the screen of the LCD 40 is cancelled,and the moving image or the intermittent image is displayed again.

The image data stored in the external storage device 26 can be readunder the control of the control CPU 60. The read image data isexpanded, and is outputted to the LCD 40 through the image reproducingunit 57.

The first image-capturing unit 12 has the connection detecting means 58,which detects the connection with the second image-capturing unit 14 ata contact point of the joint part and transmits a detection signal tothe control CPU 60.

The synchronous signal generating circuit 54 transmits timing signals tothe imaging circuit 50, the automatic control data obtaining unit 53,the image processing circuits, and so on, and also transmits synchronoussignals for the signal processing to the second image-capturing unit 14.

The second image-capturing unit 14 controls the imaging circuit 64 andthe lens drive unit 66 by a control CPU 74 in accordance with the AE,AWB and AF information obtained by the automatic control data obtainingunit 53 of the first image-capturing unit 12. The control CPU 74controls the gain adjustment circuit 70 in such a way that the level ofthe video signal of the second image-capturing unit 14 is equal to thelevel of the video signal of the first image-capturing unit 12 inaccordance with the information from the first image-capturing unit 12.It is possible to use the control CPU 60 of the first image-capturingunit 12 without providing the control CPU 74 of the secondimage-capturing unit 14.

Alternatively, the second image-capturing unit 14 may also be providedwith an automatic control data obtaining unit 75 so that the automaticcontrol data obtaining unit 75 can determine the AE, AWB, and AFaccording to the image signals outputted from the imaging circuit 64. Ifthe second image-capturing unit 14 has the automatic control dataobtaining unit 75, it is also possible to share the operation to obtainthe automatic control data between the first and second image-capturingunits 12 and 14. For example, the automatic control data obtaining unit53 of the first image-capturing unit 12 determines the AE and the AWB,and the automatic control data obtaining unit 75 of the secondimage-capturing unit 14 determines the AF.

The display position adjusting device 72 is a means for correctingdiscordance between the imaging area of the imaging system of the firstimage-capturing unit 12 and the imaging area of the imaging system ofthe second image-capturing unit 14. The display position adjustingdevice 72 changes the output extraction area (position) of the CCD inthe imaging circuit 64, and adjusts the display position of the secondimage-capturing unit 14 (the output extraction position of the CCD) sothat the closest subject can overlap with each other on the imageobtained through the two optical systems directed to the same subject.The second image-capturing unit 14 is provided with the means forcorrecting the discordance between two images for the reasons statedbelow. When the image-capturing optical system of the firstimage-capturing unit 12 and the image-capturing optical system of thesecond image-capturing unit 14 are united, it is difficult to completelymake their images correspond to one another due to the error of theattachment position of each CCD, and so on.

More specifically, while the image obtained by the imaging system of thefirst image-capturing unit 12 and the image obtained by the imagingsystem of the second image-capturing unit 14 are displayed to overlapeach other on the LCD 40, the image extraction position (area) and theangle of the imaging system of the second image-capturing unit 14 areadjusted by operating the cross key 48. The amount adjusted by thedisplay position adjusting device 72 is stored in the memory 56 (or theinternal memory of the control CPU 60) so as to maintain the adjustedstate.

The first image-capturing unit 12 and the second image-capturing unit 14may be provided with power sources 77 and 78, respectively.Alternatively, the power source 77 of the first image-capturing unit 12can also be used to supply the second image-capturing unit 14 with thepower without the power source 78.

FIG. 3 shows an example in which the two image-capturing units 12 and 14are connected. As described above, there is no limitation on the numberof units to be connected. In the image-capturing apparatus 10 composedof multiple image-capturing units, the second image-capturing unit 14and the subsequent image-capturing units also record the images insynchronism with the release signal outputted from the firstimage-capturing unit 12. In the continuous image-recording mode, theimage record timing of each image-capturing unit is offset by apredetermined time from the image record timing of the precedingimage-capturing unit. The continuous image-capturing is performed withtime lags between the units.

If a plurality of image-capturing units capture the image cooperatively,the synchronous signals outputted from the synchronous signal generatingcircuit 54 drive the circuits of the other image-capturing units.Alternatively, the second and the subsequent image-capturing units maybe provided with synchronous signal generating circuits 80 so that thesynchronous signals from the first image-capturing unit 12 cansynchronize the synchronous signal generating circuits 80 of the secondand the subsequent image-capturing units.

If zoom lenses are used for the taking lenses 16 and 28, the zoomcontrol signals from the first image-capturing unit 12 are preferablysupplied to the other image-capturing units to control zoomingmechanisms so that the zooming magnifications of the image-capturingunits 12 and 14 can be equal during the operation of a zoom control part(not shown) of the first image-capturing unit 12.

If a plurality of image-capturing units are connected, the amount ofimage data obtained by one image-recording differs according to thenumber of the connected units. For this reason, it is desirable toprovide a means for automatically changing the number of possible shots,which is shown to the operator, in accordance with the number ofconnected image-capturing units and the available capacity of the memoryin the external storage device 26.

FIG. 4 shows another embodiment of the image-capturing apparatus 10 inFIG. 1. As shown in FIG. 4, it is preferable to rotatably support a lenspart (an imaging part) 82 of the second image-capturing unit 14horizontally (and vertically as the need arises) and provide a means(equivalent to an optical axis angle changing means) for automaticallysetting the rotational angle of the lens part 82 according to the viewangle of the lens 28. In this embodiment, the image processing meansinside the camera or the image processing means outside the cameracombines the images captured by the first and second image-capturingunits 12 and 14 to thereby obtain a panoramic image.

Preferably, the lens part 82 of the second image-capturing unit 14 isslidable horizontally, and there is provided a means (equivalent to alens interval changing means) for setting the interval between thelenses 16 and 18 of the first and second image-capturing units 12 and14.

As described with reference to FIG. 1, the joint holes 36 and the slot34 are formed at the side of the second image-capturing unit 14 so thata third image-capturing unit 84 can be connected to the secondimage-capturing unit 14 as shown in FIG. 5. Two joint holes 85 and aslot 86, which are the same as the joint holes 36 and the slot 34, areformed in the third image-capturing unit 34 so that it can be connectedto a fourth image-capturing unit (not shown). There is no limitation onthe number of image-capturing units to be connected.

As shown in FIG. 6, it is also possible to connect an electronic flashunit 88, which does not include any imaging means, instead of theimage-capturing unit including the imaging means. The electronic flashunit 88 has a light emitting part 89, two joints 90 and a connector 91,and the electronic flash unit 88 can be connected to the secondimage-capturing unit 14 or the first image-capturing unit 12. Two jointholes 92 and a slot 93, which are the same as the joint holes 36 and theslot 34, are formed in the electronic flash unit 88 so that it can befurther connected to another unit. According to this structure, it ispossible to omit the electronic flash 18 in the first image-capturingunit 12, and connect the electronic flash unit 88 as the need arises orprovide an electronic flash in the second and the subsequentimage-capturing units.

A description will now be given of the operation of the above-describedimage-capturing apparatus.

TABLE 1 shows a list of modes in the image-capturing apparatus accordingto the present embodiment.

TABLE 1 Mode Operation Single unit Normal image-capturing Multiple ThreeA plurality of image-capturing units capture units dimensional images atthe same time to obtain a plurality of images from different viewpoints.Panorama The first and second image-capturing units capture images atthe same time with the optical axis of the second image-capturing unitbeing inclined, thereby joining two images. Pan-focus A plurality ofimage-capturing units capture images at the same time at differentfocuses to compose an image with a broad focusing area. Dynamic range Aplurality of image-capturing units captures expansion images at the sametime under different exposure conditions to compose an image with abroad dynamic range. Special effects Depth information is extracted fromimages (extract depth that are captured at the same time by ainformation) plurality of image-capturing units, and image processingsuch as gradation is performed according to the depth. Multi-zooming Aplurality of image-capturing units (lenses) capture images at the sametime with different focal lengths (view angles). (A main subject iscaptured at a high resolution.) Continuous A plurality ofimage-capturing units are image- driven at preset time intervals tocapturing continuously capture images. Recording File merging A sequenceof related files are recorded as one image file. Separate file Relatedfiles are separately recorded, and related file names are given to therelated files. Display Single A piece of image file data is displayed.Multiple Multiple pieces of image file data are displayed side by side.Overlap A plurality of overlapping semitransparent images are displayed.The image position is adjusted. Parallax barrier A parallax barrier isformed on an image display layer to display a three-dimensional image.Flashing Single flashing Only one flash lamp flashes. Simultaneous Aplurality of flash lamps flash flashing simultaneously.

A description will be given of the functions of the image-capturingapparatus 10 with reference to TABLE 1.

The first image-capturing unit 12 can be separated from the secondimage-capturing unit so that it can be used as a normal camera. In thiscase, the external storage device 26 is mounted in the slot 22, and thecaptured image data is stored in the external storage device 26.

If the first image-capturing unit 12 is connected to one or more ofimage-capturing units such as the second image-capturing unit 14, theimage-capturing apparatus 10 can be used in a variety of modes such as athree dimensional mode and a panoramic mode. In the three dimensionalmode, two image-capturing units capture a right-eye image and a left-eyeimage at the same time to thereby obtain two images from different viewpoints.

In the panoramic mode, the optical axis of the second image-capturingunit 14 is inclined to the outside with respect to the optical axis ofthe first image-capturing unit 12, and the first image-capturing unit 12and the second image-capturing unit 14 capture two images at the sametime. The two images are processed and joined to thereby obtain apanoramic image, which is long in the landscape orientation.

In the pan-focus mode, a plurality of image-capturing units captureimages at different focus positions, and the focused areas of the imagesare combined to obtain an image, which is focussed over the whole areaof the image. In the dynamic range expansion mode, a plurality ofimage-capturing units capture images at the same time under differentexposure conditions, and the data on the images are combined to composeone image with a broad dynamic range. In the special effect mode, thedepth distribution information is extracted from images, which arecaptured at the same time by a plurality of image-capturing units.According to the depth values, the special effects such as the blurringare performed for an area (e.g., the background area), which is not at aspecific distance, in order to emphasize the main subject.

In the multi-zoom mode, a plurality of image-capturing units (lenses)captures images at the same time with different focal lengths (viewangles) thereof. In this mode, the main subject is imaged at a highmagnification (telescopically), and the image data of the images areconnected to one another so that the main subject can be enlarged anddisplayed with a high image quality at the reproduction. The imageprocessing method in the pan-focus mode, the dynamic range expansionmode, the special effect mode and the multi-zoom mode is not onlyapplied to the image-capturing apparatus 10 but it may also be appliedin a variety of image processing techniques which process multiplepieces of image data. In the continuous image-capturing mode, aplurality of image-capturing units are driven one-by-one atpredetermined time intervals as described previously.

The image data obtained in each image-capturing mode is recorded in oneof the following two modes: the file merging mode and the separate filemode. In the file merging mode, a sequence of related files (image datafiles), which are obtained at the same time or continuously by aplurality of image-capturing units, is recorded as one image file.

In the separate file mode, the related files obtained by theimage-capturing units are recorded separately, and related file namesare automatically given to the related files. For example, “L” is addedto a name of a data file for left-eye images, and “R” is added to a nameof a data file for right-eye images.

Preferably, the file names that are given automatically in the filemerging mode, and the file names that are given automatically in theseparate file mode, belong to different types so that they can bedistinguished at a first glance. The control CPU 60 manages the files.

To reproduce and display the image, it is possible to select one of thefollowing four modes: the single mode, the multi-mode, the overlap modeand the parallax barrier mode. In the single mode, a piece of image filedata is displayed on the screen of the LCD 40. In the multi-mode, aplurality of image files are arranged on the screen of the LCD 40. Inthe overlap mode, a plurality of semi-transparent images are displayedto overlap each other on the screen of the LCD 40. The operator canadjust the positions of the images by the display position adjustingdevice 72 while looking at the overlapping images.

In the parallax barrier mode, the parallax barrier is formed on theparallax barrier display layer of the LCD 40. And the image pattern, inwhich the strip-shaped image fragments of the left-eye images and theright-eye images are alternately arranged in conformity with the pitchof the parallax barrier, is displayed to display three-dimensionalimages.

The flash lamps flash in the single flashing mode or the simultaneousflashing mode. Only one flash lamp flashes in the single flashing mode,whereas a plurality of flash lamps flash in the simultaneous flashingmode.

In addition to the modes shown in FIG. 7, the image-capturing apparatushas functions as described below.

It is possible to add a means for prohibiting the image-capturing orrecording of any image-capturing unit to selectively use desiredimage-capturing units. In this case, the power for the unusedimage-capturing is preferably shut off to prevent the waste of power.

It is possible to provide a file management means for joining multiplepieces of image data, which are captured with time lags in the singlelens mode, to thereby obtain one image file, or the multiple pieces ofimage data are separately stored in a plurality of image files withrelated file names.

In the image-capturing apparatus 10 stated above, a non-contactcommunication means (a wireless communication means), which useselectromagnetic waves such as infrared rays and radio waves in order totransmit the data between the first image-capturing unit 12 and thesubsequent image-capturing units. Consequently, the separatedimage-capturing units can capture the images at the same time.

In these embodiments, the LCD is used as the image display, but anelectroluminescence (EL) display, a light emitting diode (LED) display,a plasma display, or the like may also be used as the image display.

In the above description, the apparatus (the electronic camera) convertsthe image light representing the subject into electric signals by theimaging device such as the CCD to thereby obtain the electronic image.The present invention may also be applied to an image-capturingapparatus, which uses a camera (a silver halide camera) for recordingthe image light on a photosensitive material such as photographic film.The present invention may be applied not only to the apparatus thatcaptures still images but also to the apparatus that captures movingimages.

As set forth hereinabove, the image-capturing apparatus of the presentinvention modularizes the image-capturing units provided with theimage-capturing optical systems. The first image-capturing unit, whichis capable of functioning as the normal image-capturing apparatus, isconnected to a plurality of image-capturing units as the need arises.Therefore, the image-capturing apparatus of the present invention isportable when it is used as the normal single lens camera. Moreover, theimage-capturing units can easily be connected to the firstimage-capturing unit to expand the functions so that the image-capturingapparatus can be used as the multiple lens camera. This eliminates thewaste in the structure of the image-capturing apparatus.

In particular, a plurality of image-capturing units are synchronouslydriven to easily obtain a sequence of related images. It is thereforepossible to easily obtain the three-dimensional image and the panoramicimage. Moreover, it is possible to obtain the depth information from themultiple pieces of image data to perform the special effects such as theblurring of the background.

In addition, there is provided the means for correcting the discordancebetween the optical systems of the connected image-capturing units inorder to obtain the high-quality three-dimensional image and panoramicimage.

It should be understood, however, that there is no intention to limitthe invention to the specific forms disclosed, but on the contrary, theinvention is to cover all modifications, alternate constructions andequivalents falling within the spirit and scope of the invention asexpressed in the appended claims.

1. An image-capturing apparatus, comprising: a first image-capturingunit having a first image-capturing optical system; and a secondimage-capturing unit having a second image-capturing optical system, thesecond image-capturing unit being detachably connected to the firstimage-capturing unit in a multi-lens camera mode; wherein the firstimage-capturing unit is an electronic camera, said first image-capturingunit comprising: joint holes for connecting with joints of the secondimage-capturing unit, and an interface for transmitting data between thefirst image-capturing unit and the second image-capturing unit, whereinthe interface can also accommodate writing and reading data to and froman external storage device detachably connected to the electronic camerawhen the image capturing apparatus is not in a multi-lens camera mode,wherein each of the first and second image-capturing optical systemscomprises a zoom lens; and the image-capturing apparatus furthercomprises a lens controller for driving the zoom lenses of the first andsecond image-capturing optical systems to equalize zoomingmagnifications of the first and second image-capturing optical systems,wherein said first and second image-capturing units cooperativelyprovide at least one of a panoramic imaging mode and a three-dimensionalimaging mode when operatively connected in the multi-lens camera mode,and wherein full image data from both the first and secondimage-capturing units are captured simultaneously and the simultaneouslycaptured image data are stored while in the multi-lens camera mode. 2.The image-capturing apparatus as defined in claim 1, wherein the secondimage-capturing unit has a connecting part capable of detachablyconnecting to a third image-capturing unit having a thirdimage-capturing optical system.
 3. The image-capturing apparatus asdefined in claim 1, further comprising: a connection detector fordetecting that the first image-capturing unit is connected to at leastthe second image-capturing unit; and a controller for synchronizing orinterlocking image-capturing operation of the first image-capturing unitand at least the second image-capturing unit.
 4. The image-capturingapparatus as defined in claim 1, further comprising at least one of: alens interval changer for adjusting an interval between the first andsecond image-capturing optical systems; and a optical axis angle changerfor adjusting an angle of an optical axis of the second image-capturingoptical system with respect to an optical axis of the firstimage-capturing optical system.
 5. The image-capturing apparatus asdefined in claim 1, wherein each of the first and second image-capturingunits has a power source.
 6. The image-capturing apparatus as defined inclaim 1, further comprising: a power supplying device for supplyingpower from a power source of the first image-capturing unit to at leastthe second image-capturing unit.
 7. The image-capturing apparatus asdefined in claim 1, wherein the second image-capturing unit records animage at the same time as the first image-capturing unit does insynchronism with an image-recording start signal outputted from thefirst image-capturing unit.
 8. The image-capturing apparatus as definedin claim 1, wherein an image capture timing of the secondimage-capturing unit is offset from a reference image capture timing ofthe first image-capturing unit by a predetermined time to therebycontinuously capture images with the first and second image-capturingunits when in continuous image-capturing mode.
 9. The image-capturingapparatus as defined in claim 1, wherein the first image-capturing unitcomprises at least one of: an AE device for measuring an AE value forcontrolling automatic exposure; an AWB device for measuring an AWB valuefor automatically controlling white balance; and an AF device formeasuring an AF value for automatically controlling a focal point;wherein the first image-capturing unit automatically controls at leastone of the exposure, the white balance and the focal point in accordancewith said at least one of the AE value, the AWB value and the AF valueobtained by the first image-capturing unit.
 10. The image-capturingapparatus as defined in claim 9, wherein the second image-capturing unitcomprises at least one of: an AE device for measuring an AE value,separate from the AE device of the first image-capturing unit, forcontrolling automatic exposure; an AWB device for measuring an AWBvalue, separate from the AWB device of the first image-capturing unit,for automatically controlling white balance; and an AF device formeasuring an AF value, separate from the AF device of the firstimage-capturing unit, for automatically controlling a focal point;wherein the first image-capturing unit and the second image-capturingunit share measuring operations and measured results.
 11. Theimage-capturing apparatus as defined in claim 1, wherein each of thefirst and second image-capturing optical systems comprises a non-contactcommunication device for transmitting information between the firstimage-capturing unit and the second image-capturing unit by usingelectromagnetic waves including image data from the secondimage-capturing unit to the first image-capturing unit.
 12. Theelectronic camera as defined in claim 1, wherein the external storagedevice is detachably attached to the electronic camera through a slot.13. An image-capturing unit capable of being detachably attached to theelectronic camera of claim 1, the image-capturing unit comprising: animaging part including an imaging device for converting a light from asubject into an electric signal, the imaging part being constructed inthe same manner as the image-capturing optical system loaded in theelectronic camera; and a joint capable of jointing with a connectingpart of the electronic camera.
 14. The image-capturing unit of claim 13,further comprising: a second connecting part to which a thirdimage-capturing unit is connected; and a third information transmissionpart for transmitting data between the second image-capturing unit andthe third image-capturing unit connected to the second image-capturingunit through the second connecting part.
 15. An electronic flash unitcapable of being detachably attached to the electronic camera of claim1, the electronic flash unit flashes in response to an image-recordingstart signal outputted from the first image-capturing unit.
 16. Theimage-capturing apparatus as defined in claim 1, wherein each of thefirst and second image-capturing units comprises an imaging device forconverting a light from a subject into an electric signal, and capturesan image as an electronic image.
 17. The image-capturing apparatus asdefined in claim 16, further comprising: an image position adjuster foradjusting a position of an image captured by the second image-capturingunit with respect to a position of an image captured by the firstimage-capturing unit.
 18. The image-capturing apparatus as defined inclaim 16, further comprising: an image display; and an adjusting devicefor displaying, on the image display, the image captured by the firstimage-capturing optical system and the image captured by the secondimage-capturing optical system to overlap one another, the adjustingdevice adjusting at least one of an image extracting position and animage extracting angle of the second image-capturing optical system. 19.The image-capturing apparatus as defined in claim 18, further comprisinga storage device for storing an amount adjusted by the adjusting device.20. The image-capturing apparatus as defined in claim 16, furthercomprising: an image display; and an adjusting device for displaying, onthe image display, the image captured by the first image-capturingoptical system and the image captured by the second image-capturingoptical system to overlap one another, the adjusting device adjusting adirection of an optical axis of the second image-capturing opticalsystem.
 21. The image-capturing apparatus as defined in claim 16,wherein the second image-capturing unit comprises a gain adjuster foradjusting a gain of a video signal to equalize a video signal level ofthe second image-capturing unit to a video signal level of the firstimage-capturing unit.
 22. The image-capturing apparatus as defined inclaim 16, further comprising: an image display having a parallax barrierdisplay layer on a display plane, the parallax barrier display layerdisplaying a parallax barrier having a pattern in which lighttransmissible parts and light shielding parts are arranged alternately;and a signal processor for displaying, on the image display means, oneof an image pattern in which strip-shaped image fragments representing aleft-eye image and a right-eye image are arranged alternately, and animage pattern in which strip-shaped image fragments representing aplurality of images are arranged in order; wherein one of an imagecapable of being seen three-dimensionally and an image capable of beingseen differently according to viewing directions is displayed.
 23. Theimage-capturing apparatus as defined in claim 16, wherein the first andsecond image-capturing units capture images at different focalpositions, and focused areas in the images are combined to compose animage that is focused over the whole image.
 24. The image-capturingapparatus as defined in claim 16, wherein depth distribution informationis extracted from the images captured by the first and secondimage-capturing units to perform special effects for areas that are notat a predetermined image-capturing distance.
 25. The image-capturingapparatus as defined in claim 16, further comprising a shot numberdisplay for displaying a number of possible shots according to a numberof connected image-capturing units.
 26. The image-capturing apparatus asdefined in claim 16, further comprising a file manager for recording asequence of image data, captured by the first and second image-capturingunits simultaneously or continuously, in an image file and automaticallygiving a file name to the image file, the file name beingdistinguishable from a file name of an image file in which one piece ofimage data is recorded.
 27. The image-capturing apparatus as defined inclaim 16, further comprising a file manager for recording a sequence ofimage data, captured by the first and second image-capturing unitssimultaneously or continuously, in separate image files andautomatically giving file names to the separate image files, the filenames indicating that the separate image files are related to oneanother.
 28. The image-capturing apparatus as defined in claim 1,wherein in the panoramic imaging mode, an optical axis of the secondimage-capturing unit is inclined outside of an optical axis of the firstimage-capturing unit.
 29. The image-capturing apparatus as defined inclaim 1, wherein the first and second image-capturing unitscooperatively provide both of the panoramic imaging mode and thethree-dimensional imaging mode when operatively connected in themulti-lens camera mode.
 30. The image-capturing apparatus as defined inclaim 1, wherein the second image-capturing unit includes an interfacecapable of transmitting data to and from a third-image capturing unitwhen the third-image capturing unit is detachably attached to the secondimage-capturing unit and capable of transmitting data to and from theexternal storage device detachably attached when the thirdimage-capturing unit is not attached to the second image-capturing unit.31. The image-capturing apparatus as defined in claim 1, wherein thesecond image-capturing unit includes a lens part that is horizontallyslidable or horizontally rotable or both.
 32. The image-capturingapparatus as defined in claim 1, wherein the first image-capturing unitincludes a first control CPU configured to control operations of thefirst image-capturing optical system, and wherein the secondimage-capturing unit includes a second control CPU, separate from thefirst control CPU, configured to control operations of the secondimage-capturing optical system in accordance with information providedfrom the first control CPU.
 33. The image-capturing apparatus as definedin claim 32, wherein the first control CPU is configured to directlycontrol operations of the second image-capturing optical system withoutinvolvement from the second control CPU.
 34. An image-capturingapparatus, comprising: a first image-capturing unit having a firstimage-capturing optical system; and a second image-capturing unit havinga second image-capturing optical system, the second image-capturing unitbeing detachably connected to the first image-capturing unit in amulti-lens camera mode; wherein the second image-capturing unit isconnected with the first image-capturing unit, so that the firstimage-capturing unit and the second image-capturing unit are controlledin accordance with image information obtained by the firstimage-capturing unit and the second image-capturing unit, wherein thefirst image-capturing unit comprises a first connecting part thatmechanically and directly connects a second connecting part of thesecond image-capturing unit so as to form a single unit, wherein thefirst connecting part is such that an external storage device can bedetachably connected to the first image-capturing unit when the secondimage-capturing unit is not connected to the first image-capturing unit,wherein said first and second image-capturing units cooperativelyprovide at least one of a panoramic imaging mode and a three-dimensionalimaging mode when operatively connected in the multi-lens camera mode,and wherein full image data from both the first and secondimage-capturing units are captured simultaneously and the simultaneouslycaptured image data are stored while in the multi-lens camera mode. 35.The image-capturing apparatus as defined in claim 34, wherein each ofthe first and second image-capturing units comprises an imaging devicefor converting a light from a subject into an electric signal, andcaptures an image as an electronic image.
 36. The image-capturingapparatus as defined in claim 35, wherein the second image-capturingunit comprises a gain adjuster for adjusting a gain of a video signal toequalize a video signal level of the second image-capturing unit to avideo signal level of the first image-capturing unit.
 37. Theimage-capturing apparatus as defined in claim 35, further comprising: animage display having a parallax barrier display layer on a displayplane, the parallax barrier display layer displaying a parallax barrierhaving a pattern in which light transmissible parts and light shieldingparts are arranged alternately; and a signal processor for displaying,on the image display means, one of an image pattern in whichstrip-shaped image fragments representing a left-eye image and aright-eye image are arranged alternately, and an image pattern in whichstrip-shaped image fragments representing a plurality of images arearranged in order; wherein one of an image capable of being seenthree-dimensionally and an image capable of being seen differentlyaccording to viewing directions is displayed.
 38. The image-capturingapparatus as defined in claim 35, wherein the first and secondimage-capturing units capture images at different focal positions, andfocused areas in the images are combined to compose an image that isfocused over the whole image.
 39. The image-capturing apparatus asdefined in claim 35, wherein depth distribution information is extractedfrom the images captured by the first and second image-capturing unitsto perform special effects for areas that are not at a predeterminedimage-capturing distance.
 40. The image-capturing apparatus as definedin claim 35, further comprising a shot number display for displaying anumber of possible shots according to a number of connectedimage-capturing units.
 41. The image-capturing apparatus as defined inclaim 35, further comprising a file manager for recording a sequence ofimage data, captured by the first and second image-capturing unitssimultaneously or continuously, in an image file and automaticallygiving a file name to the image file, the file name beingdistinguishable from a file name of an image file in which one piece ofimage data is recorded.
 42. The image-capturing apparatus as defined inclaim 35, further comprising a file manager for recording a sequence ofimage data, captured by the first and second image-capturing unitssimultaneously or continuously, in separate image files andautomatically giving file names to the separate image files, the filenames indicating that the separate image files are related to oneanother.
 43. The image-capturing apparatus as defined in claim 34,wherein in the panoramic imaging mode, an optical axis of the secondimage-capturing unit is inclined outside of an optical axis of the firstimage-capturing unit.
 44. The image-capturing apparatus as defined inclaim 34, wherein the first and second image-capturing unitscooperatively provide both of the panoramic imaging mode and thethree-dimensional imaging mode when operatively connected in themulti-lens camera mode.
 45. The image-capturing apparatus as defined inclaim 34, wherein the second image-capturing unit includes a thirdconnecting part capable of being used to connect with a third-imagecapturing unit when the third-image capturing unit is detachablyattached to the second image-capturing unit and capable of being used toconnect with the external storage device when the third-image capturingunit is not attached to the second image-capturing unit.
 46. Theimage-capturing apparatus as defined in claim 34, wherein the secondimage-capturing unit includes a lens part that is horizontally slidableor horizontally rotable or both.
 47. The image-capturing apparatus asdefined in claim 34, wherein the first image-capturing unit includes afirst control CPU configured to control operations of the firstimage-capturing optical system, and wherein the second image-capturingunit includes a second control CPU, separate from the first control CPU,configured to control operations of the second image-capturing opticalsystem in accordance with information provided from the first controlCPU.
 48. The image-capturing apparatus as defined in claim 47, whereinthe first control CPU is configured to directly control operations ofthe second image-capturing optical system without involvement from thesecond control CPU.